Jesper, 2 days ago, I was doing the same thing, same problem, but with composite viewer. Here is what I did...
I create my screenshot camera while I create my main CompositeViewer and its children Viewers. When I create this screenshot viewer, I set its nodemask to 0 - by default, it won't render. I then trigger screenshot by placing a graphics operation into graphics context's operation queue, which saves an osg::Image. This image will then becomes texture of a quad. Right after screenshot completes, I trigger another event which does: * Iterate through compositeviewer, set all viewers' masks to 0. * Set nodemask of screenshot viewer to 0xffffffff * Also set things like setCameraWithFocus, etc. There is no flicker. I have no access to code right now, I may post an example later tonight. HTH Ismail On Wed, Apr 15, 2009 at 1:52 PM, Jesper D. Thomsen <[email protected]> wrote: > Hi all, > > I have an application where I use an osg::viewer for a single viewport of a > model. The camera for the viewer is created like this: > > ------------------------------ > > // Init a new Camera (Master for this View) > > camera = mViewer->getCamera(); > > // Assign Graphics Context to the Camera > > camera->setGraphicsContext(gc); > > // Set the viewport for the Camera > > camera->setViewport( > > new osg::Viewport(traits->x, traits->y, traits->width, traits->height)); > > // Add the Camera to the Viewer > > mViewer->setCamera(camera.get()); > > ------------------------------- > > I have created a function which will be used to both take high-res > screenshots of the main viewport and to make renderings from other cameras > defined in the model (not osg::camera's, just a camera class defining a > camera view). I wanted to do this by creating a new osg::camera on the fly > and disabling to main viewer camera in order to not have the viewport > redrawn while making a rendering/screenshot. If I do not disable the > viewer-camera by using setnodemask, the following code works but the > contents of the main viewport disappear until the next normal frame() is > called, which causes some naste blinking of the viewport, when recording > video from it. When I use setnodemask to try to disable the viewer camera, I > just get a uniform grey osg::Image. I'm somewhat new to OSG, so it is > probably some simple error. The source code for my screenshot/rendering > function can be found below. > System data: Viste 64, OSG 2.6.1, Visual Studio 2005 sp1. > > > bool > > CModelView::CreateOSGImageSnap(int p_width, int p_height, double p_left, > double p_right, > > double p_bottom, double p_top, double p_near, double p_far, > > double p_eye_pivot_0, double p_eye_pivot_1, double p_eye_pivot_2, > > double p_eye_eulerpar_0, double p_eye_eulerpar_1, double p_eye_eulerpar_2, > > double p_eye_eulerpar_3, double p_eye_dist, bool p_ortho, osg::Image* > p_image) > > { > > osg::ref_ptr<osg::Camera> t_camera = new osg::Camera; > > osg::ref_ptr<osg::Group> t_parent = new osg::Group; > > unsigned int t_samples = 0; > > unsigned int t_colorSamples = 0; > > t_camera->setViewport(0,0,p_width,p_height); > > if(p_ortho){ > > t_camera->setProjectionMatrixAsOrtho(p_left,p_right,p_bottom,p_top,p_near,p_far); > > }else{ > > t_camera->setProjectionMatrixAsFrustum(p_left,p_right,p_bottom,p_top,p_near,p_far); > > } > > osg::Matrixd t_matrix = > osg::Matrixd::translate(-(osg::Vec3d(p_eye_pivot_0,p_eye_pivot_1,p_eye_pivot_2)))* > > osg::Matrixd::rotate((osg::Quat(p_eye_eulerpar_1,p_eye_eulerpar_2,p_eye_eulerpar_3,p_eye_eulerpar_0)).inverse())* > > osg::Matrixd::translate(0.0,0.0,-p_eye_dist); > > t_camera->setViewMatrix(t_matrix); > > t_camera->setRenderOrder(osg::Camera::PRE_RENDER); > > t_camera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT); > > t_camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF); > > t_camera->setClearColor( > osg::Vec4(GetBackgroundColor()[0],GetBackgroundColor()[1],GetBackgroundColor()[2],1.0) > ); > > p_image->allocateImage(p_width, p_height, 1, GL_RGBA, GL_UNSIGNED_BYTE); > > t_camera->attach(osg::Camera::COLOR_BUFFER, p_image, t_samples, > t_colorSamples); > > t_camera->setPostDrawCallback(new MyCameraPostDrawCallback(p_image)); > > osg::Node* t_oldroot = mOSG->getASG()->getOSGRoot(); > > t_camera->addChild(mOSG->getASG()->getOSGRoot()); > > t_parent->addChild(t_camera.get()); > > mOSG->getViewer()->setSceneData(t_parent.get()); > > mOSG->getViewer()->getCamera()->setNodeMask(0x0); > > mOSG->getViewer()->frame(); > > //bool s_test = osgDB::writeImageFile(*p_image, "screenshot.bmp"); > > mOSG->getViewer()->setSceneData(t_oldroot); > > mOSG->getViewer()->getCamera()->setNodeMask(0xffffffff); > > return true; //Fixme: This should be changed to a bool describing whether > the snapshot was successful. > > }; > > > Regards, and thanks in advance. > > > Jesper D. Thomsen > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
